HyperText Markup Language (HTML) is widely used on the Web for adding structure to text documents. Browsers interpret these documents, representing the structure in media-specific ways to the user. For example, visual browsers typically display the strong element ( … ) as bold text, while text-to-speech readers might emphasize that text when pronouncing it.With the help of Cascading Style Sheets (CSS) the author may define how structural elements are to be represented, overriding the browser defaults."
XML 1.0 - Extensible Markup Language
Example of part of an XML document
Extensible Markup Language (XML) is a markup language like HTML, but instead of having a single, fixed set of elements, it allows you to define your own - or use a set made by someone else. It even allows using multiple sets within a single document - by using XML namespaces.
Some applications of XML, such as XHTML and MathML, have already become W3C Recommendations. Others are currently W3C Working Drafts.
Style sheet standards, such as CSS and XSL, offer a variety of options for specifying how XML elements are to be rendered. Standards-compliant support for direct rendering of XML is spotty in browsers, so for presenting information to humans, HTML (or XHTML) with CSS-driven styling is the way to go. XML is mostly used for machine-to-machine communication today.
XML is more flexible than HTML, primarily because of the ability to add your own elements and make your own structural systems. This makes it an ideal format for the organization of large quantities of data - it is already in use in many databases and search engines.
2.1.3.3 XHTML 1.0, 1.1, and Modularization
XHTML 1.0 is a reformulation of HTML as an XML application. XHTML 1.0 can be seen as ideologically coming from HTML 4.01, and being technically stricter because of XML’s influence.
XHTML will display in your browser identically to the equivalent HTML. You might want to use XHTML if there is any chance you’re going to need to reprocess your content, for example to send it to a PDA; XML’s stricter syntax rules make automatic processing of XHTML much easier and cheaper than ordinary HTML.
Ideologically, XHTML 1.0 inherits the following general concepts from HTML 4.01:
That presentation and document formatting should be separated via style sheets
That documents should be made accessible
That documents should be internationalized
XHTML 1.0 also uses the model of three DTDs: Strict, Transitional, and Frameset. This model originally emerged in HTML 4.0 and followed through to HTML 4.01.
Some important technical practices from XML onto XHTML includes:
That all document types are declared via the correct DOCTYPE declaration
That the structure of a conforming document contain the DOCTYPE declaration, an html element with the XHTML namespace declared, a head element including the title element, and a body element
That all elements and attribute names are written in lower case, and that all attribute values are quoted
That all non-empty elements (e.g. p, li) are properly terminated with a closing tag
That all empty elements (e.g. br, hr, img) are properly terminated with a trailing slash (
)
That documents validate against the DTD that is declared
For templates, please see Learn > Templates
XHTML 1.1 is made up of three primary parts:
The XHTML 1.0 Strict DTD (with minor modifications)
XHTML Modularization
The Ruby Annotation
If you’d like to author documents in XHTML 1.1, you can do so in a couple of ways. The first is by using the public XHTML 1.1 DTD. By doing this, your work will be extremely structured because there are virtually no presentational attributes in XHTML 1.1. The separation of structure and presentation is complete here, and all of your presentation work will go in a style sheet.
Another means of authoring documents in XHTML 1.1 is to tap into XHTML Modularization. This is the breakdown of familiar components of HTML and XHTML (such as text, tables, frames, forms) into discrete chunks. You can then write your own DTD and use only those components you require. This is extensibility in action, essentially giving you, the web author, the opportunity to customize your markup.
The Ruby Annotation is a special means of dealing with certain Asian character annotations. Ruby falls under the work being done with Internationalization.
CSS - Cascading Style Sheets
Cascading Style Sheets (CSS) is a mechanism for changing the appearance of HTML or XML elements, by assigning styles to element types, self-defined classes of elements or individual instances.
Stylesheets can be used to consistently define the appearance of an entire site. Following the introduction of CSS, the W3C recommended that layout-specific features in HTML be phased out and replaced by stylesheets, creating a simpler and more structural World Wide Web.
DOM 1 - Document Object Model Level 1
The DOM allows the full power and interactivity of a scripting language (such as ECMAScript, the standardized version of JavaScript) to be exerted on a web page. (In programming terms, the Document Object Model (DOM) Level 1 is an Application Programming Interface (API) for interacting with web pages.) It gives the scripting language easy access to the structure, content, and presentation of a document which is written in such languages as HTML and CSS.
The DOM is compatible with future improvements in technology; it will allow any scripting language to interact with whatever languages are being used in the document. This standard will not only make it easier to program dynamic HTML, but will also make adapting to future Internet technology much less painful.
ECMA Standards
2.2.1 What is the ECMA?
The European Computer Manufacturers Association (ECMA) is an organization officially founded in 1961 in order to meet the need for standardizing computer operational formats, including programming languages and input/output codes.
The ECMA is based in Geneva, Switzerland, near the headquarters of the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). In 1994, the organization’s name was changed to the ECMA - European Association for Standardizing Information and Communication Systems, in order to reflect its broader range of activities.
What does it do?
The main role of the ECMA is to develop Standards and Technical Reports in the area of information and communication technology. As ECMA is an association of companies and not an official standardization institute, they often collaborate with official national or international institutes.
ECMA Standards have been accepted as a base for international and European standards. So far more than 270 ECMA Standards and 70 Technical Reports have been published.
Of these standards 85 have been accepted as international standards by the International Organization for Standardization (ISO). In addition, 25 have been accepted as European standards by the European Telecommunications Standards Institute (ETSI).
What are the ECMA standards?
2.2.3.1 ECMAScript (standardized JavaScript)
ECMAScript is a standardized scripting language, based largely on Netscape’s JavaScript and Microsoft’s JScript. The ECMAScript standard is defined by ECMA’s Technical Committee 39 (TC-39).
The main use of ECMAScript, which is an object-based language, is to manipulate the objects in web pages which are specified by the Document Object Model (DOM). These objects (effectively, the elements which make up web pages, or the web pages as a wholes) can then be added to, deleted, moved, or have their properties changed. This lets web developers implement such effects as animated text, graphic roll-overs, and pages that change based on user input without having to be reloaded.
The current ECMAScript specification is ECMA Standard ECMA-262,
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